The disclosed embodiments of the present invention relate to transmitting and receiving a wireless communication signal, and more particularly, to a communication system with an up-converter and a digital baseband processing circuit implemented in one die separated from another die having a down-converter, and a related communication method thereof.
Because of the advance of the deep sub-micro complementary metal-oxide-semiconductor (CMOS) process, digital circuits become smaller and consume less power. That is, the process scaling allows more transistors implemented in the same area or a smaller area needed for implementing the same number of transistors. Hence, to reduce the size and prolong battery life for portable devices such as mobile phones, it is desirable to implement circuits in deep sub-micron CMOS process. Regarding the radio design, there is a strong push to convert the radio-frequency (RF)/analog intensive radio parts into more digital intensive designs to take full advantage of the process scaling.
Regarding a digital radio design, it is easier to realize a digital transmitter part because the signal source is already digital, and the only thing to be considered is the in-band signal generation; however, it is harder to realize a digital receiver part because the signal source is analog, and the receiver part needs to consider in-band signals as well as out-of-band interferences/blockers. Better integration usually means smaller device size and lower cost. However, if the radio design cannot be effectively converted into the digital design to reduce the size of the radio design, integration of the radio circuits, including the digital transmitter part and the digital receiver part, will greatly increase the production cost. For example, under a more advanced semiconductor process, integrating the transmitter part and the receiver part in the same die is not a cost-efficient design.
Thus, there is a need for an innovative communication system design which is capable of making the device smaller, cheaper, and have less current consumption through proper system partition and integration.